AES E-Library

Noise Shaping in Time-Domain Quantized LFM

SDM binary code can be derived from linear frequency modulation (LFM) using zero crossing detection and time-domain quantization. However, the jitter-like nature of this quantization process does not generally yield well-structured noise shaped characteristics compared to conventional time domain coders. The problem of improving the frequency domain performance of the error resulting from a LFM-based model is studied and further observations are made on the relationship between SDM and quantized LFM.